Trifluorochloroethylene-vinyl acetate copolymers



Patented June 17,

Thisdnv'ntion relates drolysi's ofth' acetate groups thereof. Thisapplication isa 'continuation-in-partof my 00-: pending applicationSerial No. 509,761, filed No* vember 10, 1943, now-abandoned;

Linear polymers containing halogen substituents only are extremelyhydrophobic, and filaments made from them are also of this character;Fabrics made therefrom have the serious disadvantage of not'beingcapable of absorbing mois-' ture from the 'bodyofthewearer.which givesrise to afeeling of discomfort'tojthe'wearer, especially in warm'orhotweather. In addition, the failure to' pick up "or retain small butappreciable.

amounts "of water greatly hampers the ability of the fabrics madetherefrom to recover'from any distortions produced during wear.

It is an object of this'invention' to produce novel copolymers oftrifluorochloroethylene which have {improved properties adapting themespecially for the production of filaments and fabrics havingimprovedcharacteristics, and particularly' acontrollable 'hydrophilic character,so

i that theabove-mentioned disadvantages are'substantially overcome orgreatly reduced.

In accordance with this invention, it has been found thattrifluorochloroetl ylene copolymerizes' In general,trifluorochloroethyleneand vinyl acetatemay becopolymeri'zed at room orsome:

. what higher temperatures up to about 50 C.

either in the presence of. a cataylst or under the influence ofultraviolet light, or under-the 1 influence of both catalyst andultraviolet light.

,m l im y b an r ai e' ner' ni er: oxygencompound, such as penzoyl'peroxide. The

mendniersmay be: c polymerized in bulkiorflm solutiofin' a suitablesolvent, such as "acetone;

though"longefjperiods may be necessary in car tain circumstances; I 7 vlhe following fexarnples fare illustrative' of pre ferred'proc'edures ofmaking copolyrners in accordancew'ith' this invention:

. Example 1 Aj niixturebf'fZio; parts by volume pr trii'iuorq.

w op l iir ofxi tiji fluorochloroethylene "with vin'yl aoetate'and the:product'sobtained' by" partial or complete hy- 1 2,600,683 UNITED STATESPATENT" TRIFLUoRoomlonou'rnytnfiivii fim ACETATE COPOLYMER'S Frankei"ria tn, r&n Mn bsB -i American" Viscose- Corporation, Wilmington,

DER-,acuipdratidridf Delaware stzniawmg; Application May-8; 1947,;SerialNo. 746,882

. 2i chloroethylene, 3 partsbywolume of vinyl acee and b u ibr weiehtqfam ure of equal amounts ofwlead tetr thyland benzoyl peroxide wasformedi-na su table vesse l eans; parent to ultraviolet light ,.'and;inwhichfthemix ture was heldunder pressureto maintain the monomers in theliquidpondition The contents were subjected to ultraviolet li h iatroomtem:-' perature and were-suitably shaken until the com: pletedisappearance of the liquid phase.

The'product thus obtained was soluble inace tone, chloroform, butanone;was v insoluble in alcohol and ether; and was. swelledzbyld ioxane. Thep'roductbeginsto pfien about 11 .0? and s he 1 temperature is raised itbecome s more plastic but never really melts. Up to 250 CJth e're are nosigns of decomposition. The copolymer had a degree of polymerization orabout 409 and the ti H1)? v e ..e t' m i il if 6 th ftli ffiuorochloroethylen'e' monomer in' the 'coploymer was 1:4.

Example? A mixture of I1.'3 partsf" by volume oftrifluorogchloroethylene'and 3,;"7 parts" byjvolume of vinyl acetate and40' parts by'volume' of an aqueous" solution containing 3,%: by; weightof Gardinol WA (sodium lauryl sulfate) and 9.01% by weight of uranylacetate' 'wa's sealed' in ajvessel transparent to ultraviolet light;Thefcontents' of'the tube were contirmously ag ated and subjected toultraviolet light agre -m hours. A 6'7;5%"yieldwa obtained ofaproducthaving a softenlng'tempeiature of 86C: and a melting temperatureflof1'75fj C. The product container 27 mol percent-vinyl acetate and theremainder of trl'fluorochloroethylene.

Example :3 The procedure of fl wasjf folflowed panoL-co Eiramplee Theprocedure of manner was followedwith a mixtureof 30 pafi tsby volumeoftrifluorochlo roethylene, s p rts by vo ume of vinyl acetate; and 1% ofthexcatalyst mixture, eigposure'to ultraviolet light" e'fie; ed for, aperiod of. 84 hours. The product was: acopolyiner contain;

ing 36 mol percent of vinyl acetate which softens at 80 C. and stringsat 125 0.

Example Example 6 A copolymer containing mol percent of vinyl acetateand produced as described above in Example 1, except that only 1 part ofvinyl acetate was used for 30 parts of trifiuorochloroethylene,

was extruded in fused condition at temperatures of 190 to 200 C. intofilaments of small diameter. By subjecting the filaments to stretchingduring extrusion or by after-stretching the formed and set filaments forwhich purpose they were rendered soft either by heat or solventaction,the filaments are improved in flexibility and tensile strength andexhibit molecular orientation. The filaments had a shrinkage temperatureof about 110 C.

Example 7 A copolymer containing 5 mol percent of vinyl acetate andproduced as in Example 1 except that only 1 part by volume of vinylacetate was used for 60 parts by volume of trifluorochloroethylene wasextruded in fused condition at temperatures of 200 to 220 C. into smalldiameter filaments After stretching as in Example 6, the filamentsshowed no shrinkage up to 110 C.

Example 8 A copolymer containing 12 mol percent of vinyl acetate andproduced as in Example 1 except that only 1.2 parts by volume of vinylacetate were used for 30 parts by volume of trifiuorochloroethylene wasextruded in fused condition at temperatures of 185 to 195 C. intofilaments. After stretching as in Example 6, the filaments showed noshrinkage up to 105 C.

Example 9 Ten grams of copolymer of Example 3 containing 33.1.molpercent vinyl acetate were dissolved in 100 cc. chloroform. Thissolution was then allowed to run in a fine stream, with vigorousstirring, into 250 cc. of a saturated solution of hydrogen chloride in amixture of 75% chloroform-25% methyl alcohol by volume.

The slightly turbid mixture was then refluxed for one hour and allowedto stand for sixteen hours at room temperature. The polymer wasrecovered by precipitation in 1.5 liters of isopropanol. It was removedby filtration and dried in vacuo.

Analysis shows that 25% of the available acetate groups were removed bythis procedure. The product which had solubility characteristics similarto that of the parent copolymer, became tacky at 140 0., had astring-point of 200 C. and was free of any discoloration up to 300 C.The filaments formed by stringing showed no shrinkage during subjectionto boiling water for two minutes.

Example 10 A copolymer containing 79.6 mol percent of vinyl acetate, andproduced as in Example 5 except that the molar ratio of 3:1 existedbetween the vinyl acetate and trifiuorochloroethylene in the startingmixture, was subjected to hydrolysis as in Example 9 until 50% of theavailable acetate groups were replaced by hydroxyl. The resultingproduct showed no evidence of any shrinkage, softening, or tackiness upto 160 C. A 10% (by weight) solution of the product in a mixture of 75%chloroform and methyl alcohol by volume was spun into an aqueousisopropanol coagulating bath to form filaments.

By varying the proportions between the monomers in the initial reactingmixture, products can be obtained having any desired proportion of vinylacetate therein, from less than 1% up to 99% or more. Preferably, forthe production of filaments to be used generally for making textilefabrics, it is desirable that the shrinkage as well as the softeningtemperature of the filaments thereof be safely over 100 C., and alsothat the filaments have an appreciable moisture retention of at least 3/z% by weight. For this purpose, copolymers of trifiuorochloroethylenewith at least 5 mol percent but not over 12 mol percent of the vinylacetate component are generally satisfactory. However, for otherspecialized filaments, a higher proportion of vinyl acetate may bedesired in the copolymers used. Thus, in making industrial fabrics,felts, and papers which are not subjected to temperatures above thesoftening or shrinkage temperature of the particular copolymer used,copolymers containing from 5 mol percent up to 57 mol percent of vinylacetate are useful. These copolymers may be deformed but do notcompletely lose their filamentous shape or character when subjected totemperatures below 100 C. Filaments made of such thermoplastic fibersmay be converted into yarns, fabrics, felts, and papers, with or withoutadmixture of other fibers or filaments which are not rendered plastic atany temperature or at least at the low temperatures needed for thecopolymer fibers of the present invention. After such conversion, thefibers can be bonded to reinforce the articles by heating them to thethermal tacking point of the thermoplastic copolymer fibers so that theyadhere to each other by coalescence and to any other fibers present bydeformation or adhesion.

Copolymers containing from 30 to mol percent of vinyl acetate areadvantageous in that by hydrolysis, either completely or partially, asin Example 9, materials are obtained which have shrinkage points andmelting points well above C. and moisture-retention characteristicswhich can be preselected by control of the extent of hydrolysis.

All of the copolymers of the present invention are remarkably resistantto decomposition by heat and light. The most heat-sensitiv of them showno discoloration until a temperature of 250 C. is reached and some ofthem give no sign of decomposition even at temperatures of 300 to 320 C.This characteristic places the decomposition point far above the meltingpoint of the copolymers so that molding can be readily performed evenwithout incorporation of heat stabilizers. The copolymers in the ran eof 5 to 12 mol percent vinyl acetate have the best chemical resistanceand are non-inflammable.

v In general, the copolymers produced. may be formed directly intofilaments by melt-spinning through spinneret orifices. To facilitatesuch spinning, there may be added plasticizers, heat stabilizers,lubricants and the like.

Besides converting the copolymers of trifiuorochloroethylene with vinylacetate into filaments by melt-spinning, they may be dissolved insuitable solvents and either wet or dry spun into the form of filaments.In addition, films and molded articles of any desired shape may beproduced from the copolymers by utilization of their thermoplasticity orby using a solution thereof in the solvents mentioned above. Thefilaments, films, or other structures may be formed with or withoutadmixture of pigments, fillers, plasticizers and other resins.

It is to be understood that changes and variations may be made withoutdeparting from the spirit and scope of the invention as defined by theappended claims.

I claim:

1. A material comprising a copolymer whose monomeric constituentsconsist of trifiuorochloroethylene and vinyl acetate, the copolymercontaining from 5 to 80 mol percent of vinyl acetate.

2. The material of claim 1 in which the copolymer contains from 5 to 57mol percent of vinyl acetate.

3. The material of claim 2 in the form of filaments.

4. The material of claim 1 in which the copolymer contains from 5 to 12mol percent of vinyl acetate.

5. The material of claim 4 in the form of filaments showing orientationalong the fiber axis.

6. The material of claim 1 in which the copolymer contains from 30 to 80mol percent of vinyl acetate.

7. A material comprising a copolymer whose monomeric constituentsconsist of trifluorochloroethylene and vinyl acetate, the copolymercontaining approximately mol percent of vinyl acetate.

8. The material of claim 7 in the form of filaments.

9. A material comprising a copolymer whose monomeric constituentscomprise trifluorochloroethylene and at least one compound selected fromthe group consisting of vinyl acetate and vinyl alcohol, the copolymercontaining from 5 to 80 mol percent of vinyl acetate when no vinylalcohol groups are present and, when vinyl alcohol groups are present,being derived by hydrolyzing from a copolymer containing from 5 to 80mol percent of vinyl acetate and the remainder oftrifluorochloroethylene.

10. A material in accordance with claim 9 com.. prising a hydrolyzedcopolymer in which from to 100 percent of the acetyl groups have beenremoved.

11. A material in accordance with claim 9 comprising a hydrolyzedcopolymer in which from 25 to 50 percent of the acetyl groups have beenremoved.

12. The material of claim 11 in the form of filaments.

13. A process for the production of a polymeric material which comprisescopolymerizing a mixture of polymerizable compounds consisting oftrifiuorochloroethylene and vinyl acetate in the presenc of a peroxygencompound at temperatures from room temperatures up to 50 C.

14. The process of claim 13 in" which the copolymerization is performedunder the influence of ultra-violet light.

15. The process of claim 13 in which the copolymerization is effectedunder pressure suificient to maintain the monomers in liquid condition.

16. A process in accordance with claim 13 in which thetrifluorochloroethylene-vinyl acetate copolymer is at least partiallyhydrolyzed in the presence of hydrochloric acid.

17. The process of claim 16 in which the hydrolysis is efiected bypassing a solution of the copolymer into a saturated solution ofhydrogen chloride in an organic solvent for the hydrolyzed copolymer,and the hydrolyzed copolymer being then precipitated by the introductionof the solution into a non-solvent therefor.

18. A solid polymer consisting of from about 33-72 mole percent vinylacetate and from about 67-28 mole percent chlorotrifiuoroethylene,copolymerized therein.

19. A solid polymer consisting of about 33 mole percent vinyl acetateand about 67 mole percent chlorotrifiuoroethylene copolymerized therein.

FRANK G. PEARSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,935,577 Reid Nov. 14, 19332,386,347 Roland, Jr. Oct. 9, 1945 FOREIGN PATENTS Number Country Date796,026 France Mar. 27, 1936 OTHER REFERENCES Douglas: Vinyl Resins,Industrial and Engineering Chem, March 1940, vol. 32, No. 3, page 316.

9. A MATERIAL COMPRISING A COPOLYMER WHOSE MONOMERIC CONSTITUENTSCOMPRISES TRIFLUOROCHLOROETHYLENE AND AT LEAST ONE COMPOUND SELECTEDFROM THE GROUP CONSISTING OF VINYL ACETATE AND VINYL ALCOHOL, THECOPOLYMER CONTAINING FROM 5 TO 80 MOL PERCENT OF VINYL ACETATE WHEN NOVINYL ALCOHOL GROUPS ARE PRESENT AND, WHEN VINYL ALCOHOL GROUPS AREPRESENT, BEING DERIVED BY HYDROLYZING FROM A COPOLYMER CONTAINING FROM 5TO 80 OF TRIFLUOROCHLOROETHYLENE.